Topic 1-Heart, Disease, Lifestyle

Question 1

Why do multicellular organisms need mass transport systems?

Answer 1

-diffusion across the outer membrane would be too slow due to large distance needed to travel to all cells
- mass transport systems can carry raw materials from exchange organs to body cells and remove metabolic waste

Question 2

Describe how to prepare a microscope slide

Answer 2

-use a pipette to put a drop of water onto slide (as specemin can dry out easily)
- use tweezers to place specimen onto slide
- put cover slip on
- place drop of dye just next to cover slip and it should be pulled under

Question 3

Describe how to use a light microscope. (6)

Answer 3

• clip slide onto stage
• select lowest powered objective lens with lowest magnification
  -use coarse adjustment knob to bring stage up just below objective lens
  -look down eyepiece containing ocular lens and adjust stage
• adjust focus with fine adjustment knob
• use higher objective lens for higher mag

Question 4

What is a stroke and DVT?

Answer 4

• stroke = rapid loss of brain function due to disruption in blood supply to brain (no O₂)
  -deep vein thrombosis= formation of a blood clot in a veim deep inside body/ cause by prolonged inactivity

Question 5

How are heart attacks caused?

Answer 5

• when coronary artery becomes blocked by a blood clot
• area of the heart won’t receive O2 for cardiac muscle cells do respire
  -causes myocardial infarction (heart attack)
  **if large area affected= complete heart failure occurs

Question 6

Evaluation points for data (4)

Answer 6

1. Sample size= greater no. Means more reliable
   
   • should also be representative of people with many diff characteristics
2. Variables= more controlled facters means more reliable results and more valid
   
   • only testing what you want to
3. Data collectiom- less bias involved means more valid
4. Repetition by other scientists= same results mean more reliable

Question 7

How is weight gain caused?

Answer 7

• energy intake > energy output
• excess energy is turned into fat reserves

Question 8

How is weight loss caused?

Answer 8

• if energy intake < energy output
• fat reserves comverted into energy and person loses weight

Question 9

What is lactose?

Answer 9

• disaccharide
• beta glucose and galactose
  -1,4 glycosidic bond

Question 10

What is sucrose?

Answer 10

• disaccharide
• alpha glucose and fructose
  -1,2 glycosidic bond

Question 11

Describe the structure of glycogen and its function

Answer 11

1. Polysaccharide w/ Alpha glucose with 1,4 and 1,6 glycosidic bond
2. Energy storage in animal cells
   
   • excess glucose stored as glycogen
3. Many branches so stored glucose can be released quickly by hydrolysis
4. Compact and good for storage
5. Insoluble so doesn’t cause cells to swell by osmosis

Question 12

How do triglycerides form?

Answer 12

• glycerol (alcohol) + 3x fatty acids (COOH)
• condesnation reaction and ester bond forms

Question 13

Describe HDLs

Answer 13

1. Mainly protein
2. Transport cholesterol from body tissues to liver where its recycled/excreted
3. Reduce total blood cholesterol when too high

Question 14

Describe LDLs

Answer 14

1. Mainly lipid
2. Transport chokesterol from liver to blood where it circulates until need by cells
3. Increase total blood cholesterol when too low

Question 15

Describe the structure of collagen

Answer 15

• primary structure of repeating sequence of amino acids
• 3 polypeptide chains
• coil around eachother
• chains are crosslinked together

Question 16

What is the function of collagen?

Answer 16

• provide strength and flexibility to blood vessels
• also hold walls of capillaries and alveoli close together

Question 17

Define blood pressure

Answer 17

• measure of force your blood exerts on the walls of blood vessels

Question 18

Define mass transport

Answer 18

• bulk movement of gases/ liquids in one direction via a system of vessels

Question 19

What do mass transport systems help to do?

Answer 19

• bring substances quickly from one exchange site to another
• maintain diffusion gradients
• remove waste products so there is efficient cell activity

Question 20

What is maltose?

Answer 20

• disaccharide made up of two alpha glucose monomers
• 1,4 glycosidic bonds

Question 21

What are the 4 CVD treatments?

Answer 21

• anticoagulents= lower blood clotting to reduce risk of vessels being blocked
• antihypertensives= lower blood pressure to reduce risk of damage to endothelium
• statins= lower LDL conc. and blood cholesterol which contributes to atheroma formation
• platelet inhibitors= prevent platelets clumping together to form blood clots